1. Field of the Invention
The present invention relates to a thermal image transfer sheet and a thermal image transfer recording medium for use with clothing, and more particularly, to a thermal image transfer sheet for use with clothing which provides an large including characters, symbols, and the like, with good transfer characteristics, which is superior in withstands both dry cleaning and laundering (hereinafter simply `withstanding cleaning`) on a label for carrying instructions about the care of clothing or on the clotting itself, and also to a thermal image transfer recording medium for use with clothing which is a combinations of the thermal image transfer sheet and an image-receiving member.
2. Discussion of Background
Many types of thermal image transfer sheets for use with clothing have been proposed up to the present time. In particular, in the case where a pattern-type ink layer from the thermal image transfer sheet is formed on an image-receiving member, intensive investigations have been carried out into images formed on the image-receiving member which show good capability in withstanding cleaning. At the present time, this objective is dependent upon the fixing characteristics of a binder resin which is one of the elements making up a thermal image transfer layer.
For example, the following have been proposed as binder resins:
(1) A polyamide resin and a non-crystalline polyester resin and/or an epoxy resin [Japanese Laid-Open Patent Application 61-244593); PA1 (2) A non-crystalline polyester resin with a glass transition temperature of 40.degree. C. or more and a number average molecular weight of 10,000 or less, and preferably an aromatic polyester containing a bisphenol component with a glass transition temperature of 50.degree. C. to 80.degree. C. and a number average molecular weight of 5000 or less (Japanese Laid Open Patent Application 62-13384); PA1 (3) A polymerized fatty acid type of polyamide resin (Japanese Laid Open Patent Application 62-66991); PA1 (4) At least one resin selected from the group consisting of a vinyl chloride - vinyl acetate copolymer resin, an acrylic-vinyl acetate copolymer resin, a methacrylic - vinyl acetate copolymer resin, and a vinyl acetate resin (Japanese Laid-Open Patent Application 63-56490); PA1 (5) A butyral resin (Japanese Laid-Open Patent Application 63-82786); and PA1 (6) A binder resin containing a fatty acid amide or fatty acid imide with a melting point of 120.degree. C. or more and a polyamide resin or vinyl resin with a melting point of 100.degree. C. or more (Japanese Laid Open Patent Application 63-179791).
However, the image formed from a thermal image transfer ink dispersed as a colorant in these conventional binder resins uses a material as an ink component which dissolves in the cleaning solvents (water, hot water, 1,1,1-trichloroethane, Perclene, naphtha, and the like) so that the image does not satisfactorily withstand cleaning.